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My engine builder was finishing off my 26/30 today when one of the tomei camsahfts snapped.

Has this has happened to anyone else???

I am certain this is not an insullation fault or damage due to transit as the boxes were in mint condition and there is not a mark on the camshaft.

The intake cam will be crack tested tomorrow.

Have a look at the photos, please - let me know yr thoughts. Note no oil was added to the break. The clean/fresh bit of metal in the centre was how it looked when it broke.

post-29626-1285058702_thumb.jpg

post-29626-1285058785_thumb.jpg

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https://www.sau.com.au/forums/topic/337672-tomei-camshaft-failure/
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If you say thats exactly how it looked when it snapped then it's definatley a problem with the casting. I don't know what tomei's quality control in reguards to crack testing is but this one slipped through. The dull outer area would be coolant that seeped into the crack during grinding. You can snap a perfectly good cast cam from improper installation or removal but any micro cracks in the castin will make it snap a lot easier.

happened to one of my friend's car. Engine's freshly built. Mechanic found one cam gear was very spinable while installing timing belt. Brand new cam shaft in half on engine stand. I would say its manufacturing related. Email Tomei and ask them for exchange.

instilation error is the only way.

from the look of it, where it has broken is the loaded lobe when instaling. ie cam clocked in the timing of #1 tdc.. they can get caught on the front thrust bearing/cap if not done very carefully.

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